This document discusses the hierarchical organization of living organisms from cells to tissues to organs to organ systems. It provides examples of organ systems in humans and plants like the circulatory, excretory, root and shoot systems. The key points are: 1) Organisms like humans, animals and plants are made up of organ systems that work together for functions like digestion, transport and reproduction. 2) Organ systems consist of organs which have related functions and are composed of tissues. 3) Tissues are made up of cells, which are the basic structural and functional units of all living things. 4) Damage at any level of this hierarchy affects the levels above and the organism as a whole.

1. Suggested time allotment: 4 hours
MODULE
FROM CELL TO
1 ORGANISM
Overview
There are different materials in the environment. There are also
diverse kinds of living things. This module will discuss different kinds of
living things and what they are made up of.
Organ systems work together to help organisms meet their basic
needs and to survive. The digestive system helps organisms get energy from
the food they eat. The circulatory system moves the nutrients that come
from digested food, along with blood, to the different parts of the body. How
do you think do the other organ systems work together? Do plants have
organ systems, too?
Organ systems are made up of organs that have related functions and
are grouped together. For example, the mouth, esophagus, stomach, and
intestines are organs of the digestive system. The heart, arteries and veins
are some parts that make up the circulatory system. Are there organisms
that do not have organs?
This module introduces you to the different structures that make up
an organism. These structures are formed from the grouping together of
parts whose functions are related. You will also discover in this module that
organs are still made up of even smaller parts. Anything that happens to
these small parts will affect the functioning of the organs, organ systems,
and the whole organism.
What are organisms? What makes them up?

2. Activity 1
What makes up an organism?
Objectives
In this activity, you should be able to:
1. identify the parts that make up an organism,
2. describe the function of each part, and
3. describe how these parts work together in an organism.
Materials Needed
 Writing materials
 Posters and pictures of organisms, organ systems, organs, tissues,
and cells
Procedure
Read the selection below and answer the questions that follow.
You are an organism just like the plants and animals.
Photos: Courtesy of Michael Anthony B. Mantala
Figure 1. Pictures of a human being, plant, and an animal
Grade 7 Science: Living Things and Their Environment 2
From Cell to Organism

3. Have you ever asked yourself what
makes you up and the other organisms
around you? Figure 2 shows a model of a
human torso.
Q1. What do you see?
Below are some organ systems that
you may be familiar with.
Q2. Can you identify these organ systems?
Q3. How do these organ systems work
together?
Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
Figure 2. A model of a human
torso
Photo: http://fc.amdsb.ca/~melanie_mccowan/S04B36342.2/
human-_body.jpg
Figure 3. Some Organ Systems
The circulatory system is one of the
organ systems that make up an organism. It
is made up of the heart, blood vessels, and
blood.
Figure 4 shows a model of a human
heart. Your heart is about the size of your
fist. It pumps and circulates blood to the Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
different parts of the body through the blood
vessels. Figure 4. A model of a human
heart
Grade 7 Science: Living Things and Their Environment 3
From Cell to Organism

4. Q4. What are the parts that make up a human heart?
Q5. What will happen to the heart if any of these parts is/are injured?
Q6. What will happen to the organism?
The excretory system is another
organ system that makes up an organism.
It is made up of different organs that help
the body eliminate metabolic wastes and
maintain internal balance. These organs
include a pair of kidneys. What shape do
they look like?
The kidneys are made up of even
smaller parts. Some parts eliminate wastes
that are no longer needed by the body;
other parts function in the reabsorption of
water and nutrients.
Q7. What parts make up the kidneys?
Q8. What will happen to the kidneys if any
of these parts is/are injured?
Q9. What will happen to the organism?
Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
Figure 5. A model of a human
kidney
Organs are made up of tissues. The
heart, kidneys, and the parts that make
them up are made up of tissues. Figure 6
shows a picture of a muscle tissue. This
tissue is made up of cells - the basic units
of structure and function in organisms.
Q10. What will happen to the organs if
these tissues are injured?
Q11. What will happen to the organ
systems? Photo: http://www.uoguelph.ca/zoology/
devobio/miller/013638fig6-17.gif
Q12. What will happen to the organism?
Figure 6. Muscle tissues
Grade 7 Science: Living Things and Their Environment 4
From Cell to Organism

5. Plants are also made up of
organ systems: the root and
shoot systems. The root system
absorbs water and nutrients;
the shoot system moves them to
the different parts of the plant.
Q13. In what ways are the
functions of the organ
systems of plants similar
to those of animals? Shoot System Root System
Q14. In what ways are they Photo: Courtesy of Michael Anthony B. Mantala
different? Biology Laboratory, UP NISMED
Figure 7. An orchid showing shoot and
root systems
Figure 8 shows a picture
of a flower. Flowers are the
reproductive organs of plants.
Together with the leaves and the
stems, they make up the shoot
system.
Q15. How are flowers similar to
the reproductive organs of
animals?
Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
Figure 8. A Gumamela (Hibiscus) flower
Figure 9 shows a picture of
a root tip of an orchid. What do
you think makes up this root
tip?
Q16. What is the function of the
roots?
Figure 9. A root tip of an orchid
Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
Grade 7 Science: Living Things and Their Environment 5
From Cell to Organism

6. Figure 10 shows a model of a section of a
root tip. When you get a small section of the
root tip shown above and view it under a
microscope, you will see that it is made up of
many layers of tissues. You will also see that
these tissues are composed of similar cells that
are arranged and grouped together to perform
specific functions.
Q17. What will happen to the roots if the
tissues were damaged?
Q18. What will happen to the plant?
Figure 10. A model of a section of a root tip
showing different plant tissues
Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
Take a closer look at
the models of animal and
plant cells in Figure 11. Cells
are the basic units of
structure and function of all
organisms. These cells are
grouped together to form
more complex structures:
tissues, organs, and organs
systems. Animals and plants
are very different organisms;
and yet, they are both made Animal Cell Plant Cell
up of cells. In fact, as you
will discover in the next Photo: Courtesy of Michael Anthony B. Mantala
Biology Laboratory, UP NISMED
modules, all organisms are
made up of cells. Figure 11. Models of animal and plant cells
Q19. What happens to the tissues, organs, and organ systems if these cells
are damaged or diseased?
Q20. What happens to the organism?
Grade 7 Science: Living Things and Their Environment 6
From Cell to Organism

7. Humans and animals
are organisms...
Putting them all up together…
Plants are organisms...
Photo: Courtesy of Michael Anthony B. Mantala Photo: Courtesy of Michael
Anthony B. Mantala
Plants are made up of organ Humans and animals are made
systems... up of organ systems...
Photo:
http://aarcaro.files.wordpress.com/2011/01/dwa5-
Photo: organ-systems2.gif
http://www.emc.maricopa.edu/faculty/farabee/biob
k/bean_whole_morphology.gif
Organ systems are made up
Organ systems are made up of organs...
of organs...
Photo:
http://aarcaro.files.wordpress.com/2011/01/dw
a5-organ-systems2.gif
Organs are made up of
Organs are made up of tissues...
tissues...
Photo:
http://www.tantebazar.com/imgx/simple_plant Photo:
_tissues.jpg http://www.emc.maricopa.edu/faculty/farabee/
biobk/stomTS.gif
Tissues are made up of cells... All organisms
are made up of cells.
Photo: http://www.bbc.co.uk/ks3bitesize/science/images/
Grade 7 Science: Living Things and Their Environment 7
From Cell to Organism

8. On a separate sheet of paper, draw a table similar to Table 1.
Complete the table to show the different levels of organization in an
organism. Supply the table with descriptions based on an article (or news
clip) that your teacher has asked you to bring to class and pictures (or
drawings in case pictures are not available) that come with the article. Write
your descriptions on the first column and paste the matching pictures on
the second (for animals) and third (for plants) columns. The first row on
Organisms shows an example of how you can work out the other rows.
Levels of Organization
Descriptions Pictures
Organisms are living things
and are made up of parts
that work together: organ
systems, organs, tissues,
and cells. These parts need
to function properly for
organisms to meet their
basic needs and survive.
Photo: Courtesy of Michael Anthony B. Mantala Photo: Courtesy of Michael Anthony B. Mantala
Organ Systems
Organs
Tissues
Cells
After learning the different levels of organization in organisms, try now
to reflect on the title of this module: What makes up an organism?
Q22. What are your thoughts about your place in the environment?
Grade 7 Science: Living Things and Their Environment 8
From Cell to Organism

9. Reading Materials/Links/Websites
Bright Hub Education. (2009). Science Lesson Plan: Biological Organization.
Middle School Science Lessons. Retrieved January 16 2012 from
http://www.brighthubeducation.com/
Education. (2003). The Pyramid of Life (Levels of Biological Organization).
Biology Demystified: A Self-Teaching Guide. Retrieved January 16, 2012
from http://www.education.com/
Scitable by Nature Education. (2008). Biological Complexity and Integrative
Levels of Organization. Scitable Topicpage. Retrieved February 7, 2012 from
http://www.nature.com/scitable
Grade 7 Science: Living Things and Their Environment 9
From Cell to Organism